The goal of thieves is to remove personal property, objects for example, silently and without being noticed. Previously, various technologies for preventing theft and pickpocketing have been known.
The document U.S. Pat. No. 4,884,062 discloses an alarm system for a wallet. An alarm switch comprises two electrical contacts which are arranged on two sides of the wallet. Grabbing the wallet brings the contacts together and triggers the alarm. If the owner accidentally triggers the alarm it can be switched off again via a switch.
A further alarm system is described in document U.S. Pat. No. 6,049,277. The system has two plates which are connected to each other by a cable. In the event of theft the cable is released and the alarm triggered.
Document US 2012/0169496 A1 describes a portable device with a touch-sensitive sensor. By way of the sensor a touch pattern is recorded and compared with a stored pattern. Depending on the result of the comparison an alarm is triggered.
Document WO 03/100739 A1 discloses a method of analysing the presence of objects, more particularly objects in the immediate vicinity of a user. An object to be monitored is connected to a signal emitting device. The signal emitting device produces a signal which is received by a receiver device associated with the user, more particularly his body and/or clothing. In the receiver device an output signal indicating the presence of the object is produced.
Document WO 2013/132316 A1 discloses a method of connecting objects with a virtual world in real time. A sticker is arranged on an object which can communicate wirelessly. Security against theft can be provided by way of the sticker.
Document DE 601 15 542 T2 discloses a communications unit for preventing the loss or theft of an object.
Document U.S. Pat. No. 8,467,770 B1 discloses a method and a device for securing user data on a mobile device.